There is an ‘urgent need’ to adopt regulatory limits on trans fats, according to International Agency for Research on Cancer (IARC) scientist, Dr Véronique Chajès.
Her position follows the publication of a research article, co-authored by Chajès, which concludes that higher dietary intakes of industrially produced trans-fatty acids – originating mainly from deep frying fat – may be associated with greater risk of epithelial ovarian cancer (EOC).
Junk food and cancer
Ovarian cancer is the eighth most common cancer in the world, and the eighth most common cause of cancer-related death in women.
Researchers had previously suggested that a ‘typical Western diet’, high in fats and meats and low in vegetables, might be associated with a higher risk of EOC.
In this most recent study, scientists sought to investigate the association between trans-fatty acid intake from various food sources as well as circulating biomarker levels and EOC risk.
In particular, the researchers focused on circulating levels of industrial trans elaidic acid, along with higher intakes of linoleic acid and α-linolenic acid.
Industrially-produced trans-fatty acids can be found in baked and fried foods, and pre-packaged snacks and food.
They are also found in partially hydrogenated cooking oils and fats which are often used at home, in restaurants, or in the informal food sector – such as street vendors – and are the predominant source of trans-fatty acid intake in many populations, Chajès told FoodNavigator.
“Trans-fatty acid intakes of less than 1% of total energy intake were associated with reduced risk of coronary heart disease (CHD) mortality and events, whereas intakes greater than 1% of total energy intake were associated with increased risk of CHD mortality and events.
“These trans fatty acids are of particular concern because we have now increasing evidence that they could also, at dietary intakes less than 2g/day, be associated with higher cancer risk, breast and ovarian.”
The research article, co-authored by 40 scientists (10 of which hail from the IARC), is far from the first to question the health implications of partially hydrogenated oils (PHOs).
The World Health Organization (WHO) has long been campaigning to limit PHO intake, and says that diets high in trans-fat increase heart disease risk by 21% and deaths by 28%.
While the WHO recommends total trans-fat intake be limited to less than 1% of total energy intake – which is less than 2.2g/day with a 2,000 diet – the UN agency has gone further still, urging a ban on industrial trans-fats by 2023.
In the absence of a global ban, the WHO recommends trans-fats be replaced with healthier oils and fats as a low-cost way for governments to save the lives of their citizens, Chajès explained.
“Experiences in several countries demonstrated that industrially-produced trans-fat can be replaced by healthier oils. Costs to implement best practice interventions (i.e. regulatory limits on trans-fat) are likely well under the commonly accepted thresholds of cost-effectiveness.
“WHO now recommends trans-fat elimination as a cost-effective intervention for low- and middle- income countries. Governments can eliminate the cause of 7% of cardiovascular disease globally with a low-cost investment.”
Governmental and industry intervention
From 2 April 2021, foods in the EU intended for human consumption are required to contain less than 2g of industrial trans-fat per 100g of fat.
However, certain countries have already banned PHOs, the main source of industrially produced trans-fats.
Denmark was the first to lead the charge, when it restricted industrially produced trans-fats in 2003. It was found that after the limitation, cardiovascular disease deaths declined more quickly there than in comparable countries.
A number of other countries in the European region have since followed suit. These include Sweden, which followed Denmark’s lead, and Greece, where trans fats are limited to 0.1% in school canteens.
IARC’s Chajès, however, is not convinced it is solely governments’ responsibility to bring about change.
“Based on WHO recommendations and experience gained in several countries, the food industry should replace partially hydrogenated vegetable oils, the main source of trans fat, by healthier, polyunsaturated oils,” she told this publication.
“Regulatory measures should be accompanied by government support to industry,” she continued, “including education and technical assistance to support reformulation using polyunsaturated fatty acids and monounsaturated fatty acids instead of tropic oils and hydrogenated oils.”